Those in WV making 50K or above have long voted Republican on the presidential level, haven't they?
The difference is that low income voters moved from solid D to split, especially in a shift in the Coal region of the South. This shift which began before Obama, but accelerated in 2012.
Also, as can be determined from the exit poll, lower income voters do not vote at nearly as high a rate as mid-high income voters in WV. A few decades ago, voting from this demographic was much more common.
Yes. There are still a lot of low income and working class white voters who vote Dem.
However, the shift of these voters to the Pubs will accelerate with Trump.
If Trump can manage not to lose the edge the Pubs normally have with the well-off people, he will win the election.